mineral

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

Hardness: 7 (Mohs scale); Color: Purple, violet, or lavender; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Purple, violet, or lavender
Luster: Vitreous (glass-like)

Identified April 27, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Purple, violet, or lavender; Luster: Vitreous (glass-like); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in late-stage hydrothermal veins or igneous geodes. Color is produced by gamma radiation and traces of iron substituting for silicon in the crystal lattice. Commonly found in basaltic geodes.

Uses & applications

Primarily used in jewelry (faceting and cabochons), as decorative display specimens, and in spiritual/metaphysical collecting.

Geological facts

Amethyst was considered one of the five cardinal gemstones until large deposits were found in Brazil. Its name comes from the Greek 'amethystos', meaning 'not intoxicated', as ancient Greeks believed it protected against drunkenness.

Field identification & locations

Identify in the field by its distinct purple hexagonal crystals and its ability to scratch glass (hardness 7). Common locations include Brazil, Uruguay, Zambia, and Ontario, Canada.

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